User:Gustavobaldo/Jupiter Icy moons Explorer Mission

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{{Jupiter Icy moons Explorer Mission (JUICE) [1]}}

The Jupiter Icy moons Explorer Mission (JUICE) is an ESA mission to the Jovian system that is going to spend at least three years making detailed observations of the giant gaseous planet Jupiter and three of its largest moons, Ganymede, Callisto and Europa. It was announced in 2nd May 2012 and has superseed the cancelled NASA/ESA joint effort [[1]].

It is the first large-class mission in ESA's Cosmic Vision 2015-2025 programme and is planned for launch in 2022 and arrival at Jupiter in 2030, executing a 3 years scientific mission. According to ESA's Juice yellow [2] book the missiont Objectives are:

  • Ganymede as a planetary object
  • investigation of the Jupiter system as an archetype for gas giants
  • resolve key Europa science goals focusing on surface composition and the first subsurface observations at an icy moon with the addition of two dedicated flybys
  • enhance the spatial and temporal coverage of the Jovian atmosphere and magnetosphere by the implementation of a high-latitude phase during the Callisto flyby portion of the mission.
  • characterise the potential habitable worlds Ganymede, Europa, and Callisto
  • address two of the key science themes of ESA’s Cosmic Vision (2015-2025 call for proposals):
  • “What are the conditions for planet formation and the emergence of life?”
  • “How does the Solar System work?”.

Overall mission profile

  • 06/2022 - Launch by Ariane-5 ECA + EVEE-type Cruise
  • 01/2030 - Jupiter orbit insertion
  • Jupiter tour
  • Transfer to Callisto (11 months)
  • Europa phase: 2 Europa and 3 Callisto flybys (1 month)
  • Jupiter High Latitude Phase: 9 Callisto flybys (9 months)
  • Transfer to Ganymede (11 months)
  • 09/2032 – Ganymede orbit insertion
  • Ganymede tour
  • Elliptical and high altitude circular phases (5 months)
  • Medium altitude (500 km) circular orbit (3 months)
  • Low altitude (200 km) circular orbit (1 month)
  • 06/2033 – End of nominal mission

Spacecraft

  • 3-axis stabilised
  • Power: solar panels:636-693W(EOM)
  • HGA: 3.2 m, body fixed
  • X- (8-12 GHz) and Ka (26-40GHz) bands
  • Downlink ≥ 1.4 Gbit/day
  • High delta-V capability (2700 m/s)
  • Radiation level: 240 krad /10 mm Al solid sphere
  • The rad is a deprecated unit of absorbed radiation dose, defined as 1 rad = 0.01 Gy = 0.01 J/kg. t has been replaced by the gray in most of the world. The gray (symbol: Gy) is the SI derived unit
  • Dry mass at launch: ~1800 kg
  • Key mission drivers and technology challenges:
  • Radiation
  • Power budget
  • Mass budget

Payload (11 instruments with total mass of 104 kg):

  • Narrow Angle Camera
  • Wide Angle Camera
  • Visible and Infrared Hyperspectral Imaging Spectrometer
  • Hyperspectral imaging, like other spectral imaging, collects and processes information from across the electromagnetic spectrum. Much as the human eye sees visible light in three bands (red, green, and blue), spectral imaging divides the spectrum into many more bands. This technique of dividing images into bands can be extended beyond the visible.
  • Hyperspectral sensors collect information as a set of 'images'. Each image represents a range of the electromagnetic spectrum and is also known as a spectral band. These 'images' are then combined and form a three-dimensional hyperspectral data cube for processing and analysis.
  • Ultraviolet Imaging Spectrometer
  • UV light is found in sunlight (where it constitutes about 10% of the energy in vacuum)
  • Most ultraviolet is classified as non-ionizing radiation. The higher energies of the ultraviolet spectrum from wavelengths about 10 nm to 120 nm ('extreme' ultraviolet) are ionizing, but these wavelengths are absorbed by dioxygen and other gases in the air, and thus have an extremely short path length through air
  • short wave UV blocked by oxygen, a great deal (>97%) of mid-range ultraviolet (almost all UV above 280 nm and most up to 315 nm) is blocked by the ozone layer
  • Submillimetre Wave Instrument
  • to examin microwaves around 500 GHz that originated in water molecules, molecular oxygen, atomic carbon, and carbon monoxide in space. This corresponds to wavelengths of about 0.54 to 0.61 millimeters (540 to 610 μm).
  • Laser Altimeter
  • Ice penetrating radar
  • Ground-penetrating radar (GPR) is a geophysical method that uses radar pulses to image the subsurface. This nondestructive method uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures. GPR can be used in a variety of media, including rock, soil, ice, fresh water, pavements and structures. It can detect objects, changes in material, and voids and cracks.[1]
  • GPR uses high-frequency (usually polarized) radio waves and transmits into the ground. When the wave hits a buried object or a boundary with different dielectric constants, the receiving antenna records variations in the reflected return signal.
  • The depth range of GPR is limited by the electrical conductivity of the ground, the transmitted center frequency and the radiated power. As conductivity increases, the penetration depth decreases. This is because the electromagnetic energy is more quickly dissipated into heat, causing a loss in signal strength at depth. Higher frequencies do not penetrate as far as lower frequencies, but give better resolution. Optimal depth penetration is achieved in ice where the depth of penetration can achieve several hundred meters. Good penetration is also achieved in dry sandy soils or massive dry materials such as granite, limestone, and concrete where the depth of penetration could be up to 15 m. In moist and/or clay-laden soils and soils with high electrical conductivity, penetration is sometimes only a few centimetres.
  • Magnetometer
  • Particle Package
  • to measure the numbers and energies of ions and electrons. These measurements help determine how the particles got their energy and how they were transported through Jupiter's magnetosphere
  • Detect heavy ions using stacks of single crystal silicon wafers included in all atomic substances between carbon and nickel
  • Radio and Plasma Wave instrument
  • An electric dipole antenna is used to study the electric fields of plasmas, while two search coil magnetic antennas studies the magnetic fields. The electric dipole antenna is mounted at the tip of the magnetometer boom. The search coil magnetic antennas are mounted on the high-gain antenna feed. Nearly simultaneous measurements of the electric and magnetic field spectrum allows electrostatic waves to be distinguished from electromagnetic waves.
  • Radio Science Instrument and Ultra-stable Oscillator

References[edit]

  1. ^ "JUICE". ESA.  Text " http://sci.esa.int/juice/ " ignored (help);
  2. ^ "JUICE assessment study report (Yellow Book)". ESA.  Text " http://sci.esa.int/juice/49837-juice-assessment-study-report-yellow-book/# " ignored (help);

External links[edit]

 El Salvador